CDC -- Change Capture
Sample Source Data You can take like below
Before_Data
e_id,e_name,e_Add
11,kim,bris
22,jim,mel
33,pim,syd
44,lim,canb
55,pom,pth
After_Data
e_id,e_name,e_add
11,kim,syd
22,jim,canb
33,pim,syd
44,lim,canb
55,pom,pth
Read the data in two different files. And
Go to Change Capture Stage
Select Key_id as e_id
and click on change values.
Select Values in Available Properties to add
And select e_add as value
Click Ok
Go to Output --- Drag and Drop All the required columns required.
You can drag and drop every thing here. And Click Ok
Give file name in the Target File
Compile and Run the Job
You will get the output as
e_id e_name e_add change_code
11 kim syd 3
22 jim canb 3
3 means edited data
Implementation:
1. Two input datasets are required for change data caputure
stage.
One is Old dataset
Second is New or updated dataset
2. Give in the 2 inputs to the change capture stage and the
target as a dataset.
3. Let the incoming data be sorted based on a key column(s)
for performance purpose in the change Caputure stage.
4. Upon executing the job, the data when viewed from the
dataset shows a new column added apart from the output
data. A change code column would be generated in the change
capture stage having values as 0, 1, 2, 3 which depicts the
changes on comparing the 2 input datasets such as copy(0),
Insert(1), Delete(2), Edit(3).
5. See what kind of data you need in the output target like
copy, insert, delete, edit.
6. To apply SCD Type 2 we require Start date and End date
columns.
7. The Change Capture Stage output is given to a
Transformer Stage, where 2 new columns are generated with
Effective Start Date and End Date.
8. If you need all Inserted or new data to be passed in to
a particular dataset then you need to specify an
appropriate condition in the Transformer Stage to the
outgoing link. Ex. Drop Output For insert=true
9. In the similar way other data can also be captured or a
Filter can also be used after the Transformer Stage to
filter the data into the targets based on the requirement.
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